Safety electric fuse connector



May 5, 1953 w. KORECKI SAFETY ELECTRIC FUSE CONNECTOR 2 SHEETS-SHEET 1Filed April 24, 1951 y 5, 3 w. KORECKI 2,637,793

SAFETY ELECTRIC FUSE CONNECTOR Filed April 24, 1951 2 SHEETS-SHEET 2 lfig/Z.

a2 56 I 1 7 J7 INVENTOR.

0 WALTER K RE I 60* 76b BY I Patented May 5, 1953 UNITED STATES PATENTOFFICE SAFETY ELECTRIC FUSE CONNECTOR Walter Korecki, Brooklyn; N. Y.

Application April-24, 1951; SeriaINo. 222.717

6'Claims. (Cl. 200'115.5)

This invention relates to a double fused memher for use with aconventional electric outlet receptacle.

-More particularly, the present invention proposes the construction of adouble fused member for use between the usual electric outlet receptacleand the plug of an electric appliance in a manner to provide completeprotection for the electric appliance regardless of whether the personhas an understanding of the principles of electricity or not.

Another object of the present invention proposes constructing the doublefused member to be inserted into any outlet receptacle with either sideconnected to the positive'lead of the receptacle and so automaticallyinterpose a fuse in that positive lead.

A further object of the present invention proposes constructing thedouble fused member so that it has a pair of spaced prongs which can bepressed into and pulled out 'of the outlet receptacle in a manner sothat the same can be quickly and easily transferred between outletreceptacles and be ready for instantaneous use.

.Still further, the present. invention proposes mountingfuses of loweramperageinthe fused member which are of a slightlylower amperage thanthe fuses of-the source of electric current so that if a short circuitshoulddevelopin the appliance a vfuse of the member will beblown.leaving.the main source of current intact thus eliminating the need forgroping in the-dark to find the .fuses of the main source of-e1ectriccurrent for replacement purposes.

-Anotherobject of the present invention prothe like.

further object of the present inventionproposes constructing thereceptacle so that blown fuses can be quickly and-easily replaced by newones when necessary.

Still another object of the present invention proposes constructing thereceptacle to use fuses 0fthe screw-in-type or of the'cartr'idgetype.

It is a further object of the present invention to construct a fusedelectric outlet receptacle which is simple and durable and which can bemanufactured and sold at a reasonable cost.

. Forfurther comprehension of the invention, and of the objects andadvantages thereof, reference will be had to the following descriptionand accompanying drawings, and to the appended claims in which-thevarious'novel features of the invention are more particularly set forth.

In the accompanying drawings forming a material partof this disclosure:

Fig. 1 is an elevationalview of a double fused member constructed inaccordance with the present invention.

Fig. 2 i a side viewof themember.

Fig. 3 is an enlarged'view' similarto Fig. l, but with the removablewall taken off and with a fusescrewed intoone side of the'member.

Fig. 4 is an enlargedtransverse sectional view taken on'the'line 4-4 of'Fig. Zand with a fuse 'screwedintoone side of the member.

Fig. 5 is a partial longitudinal sectional view taken on the line 55'ofFig. 4.

Fig. 6 is a longitudinal sectional view taken substantially on the line86 of Fig. 3.

Fig. '7 is an enlarged transverse sectional view taken on the line 'I-lof Fig. 2.

Fig. 8 is a perspective view of 'one of the inlet strips used in theform of the invention shown in Figs. 1 to '7.

Fig. 9 is a'perspective viewof oneof the outlet strips and associatedpart used in the form of the invention shown in Figs. 1 to '7.

Fig. 10 is a perspective view of the double fused member constructed inaccordance with a modification of the present invention.

Fig. '11 is an enlarged elevational view of Fig. 10, but with theremovable'wall taken off.

Fig. 12 is apartial longitudinal sectional view taken on the line l2l2'ofFig. 11.

Fig. 13 is a transverse sectional view taken on the line'l3l3 of Fig.11.

Fig. 14 is an inside perspective view of the removable wall usedin' theform of the invention shown in FigsIlO to 13.

Fig. 15 is a perspective view similar to Fig. 10, but illustratingastill further modification of the present invention.

' Fig. 16 is an enlarged elevational view of Fig.

15 but with the removable wall taken off and a cartridge fuse shown inposition in one of the "cavities.

Fig. 17 is a'lon'gitudinal sectional view taken 3 substantially on theline l'l-l'l of Fig. 16 with the removable wall in position.

Fig. 18 is a transverse sectional view taken on the line l8i8 of Fig.17.

Fig. 19 is a transverse sectional view taken on the line l9l9 of Fig.17.

Fig. 20 is a perspective view of one of the inlet strips used in theform of the invention shown in Figs. 15 to 19.

Fig. 21 is a perspective view of one of the outlet strips used in theform of the invention shown in Figs. 15 to 19.

The double fused member, accordingtothe first form of the presentinvention shownin Figs. 1 to 9, is designed to use fuses of the screw intype. The receptacle includes a main body 38 which is molded as anintegral unit of hardrubher, one of the Bakelite thermosetting plastics(phenol formaldehyde resin), a thermoplastic synthetic resin(polystyrene-polymer of styjrene'usually .prepareddfrom ethylene andben- 'zene). or other similar materials (natural or synthetic) havingdielectric properties.

, The front or top face of the main body 39 is "provided with aremovable wall 33. The removiable wall is preferably molded of the samedielectric material used for molding the body 313. The removable wall.33 has the same general shape as the body 3%); but is of a'peripheralsize just slightly smaller than the peripheral size of the body soas tovfit into acomplementary recess 34 in the front or top face of thebody'til. The recessv 341s of a depth corresponding to the thickness' of,the wall 33'so' that the outer face of the wall and the front or topface ofthe mainv body 30 are flush, as shown in Figs. 4,1) and 7. Theremoval wall 33 is reta'in'ed'in position'by sev- "eral screws 35 whichpass through holes in the wall and which are threaded into complementarythreaded recesses 36 formed in the main body 39. v The main body 30beneath the removable wall '33 has several cavities 31 for fuses andwhich continue into holes 38, see particularly Figs; 2 to 4, which openoutward to the opposed sides of .the main body. Positioned within eachof the cavities 3?, there is a cylindrical metallic shell .39. Theshells 39 have their axes parallel to the "axes of the respectiveholes33 and are formed .;.to include a thread] Screw-in type fuses m'are"fpa'ssed'through the holes 38 and threaded into "the metallic shells"39, as shown at the top of ,Fig. 3 and on the right side of Fig. 4. Suchfuses :40 have the usual threadedv metallic shell con- "tacts ill seeFig. 4, for making electrical contact with themetallic shells 39 whenthefuses v are screwed into position. In addition, the fuses include theusual end contacts 49 see Figs. .3 and 4. The metallic shells 39 areretained against rotating while the fuses titlare being screwed into andout of those shells by means which will become clear as this descriptionproceeds.

Means is provided on the removable wall 33 for retaining the shells 39down in position within the cavities 31. That means comprisesprojections 4! integrally molded on the inner face of the wall which arein alignment with the cavities .31. The projections cl depend into the.cavities 3'! and have their bottom ends rounded, see Figs. .5 and 6, tofit snugly over the top of the metallic shells-39. From Figs. 4 and 5,it is apparent that the outer portions of thecavities 3; are comewhatdeeper thanthe inner portions thereof re .taining. the shells as frommoving axially inward "strip 50. 7 '50 is secured to the lug 49 of itsrespective shell recesses.

within the cavities and holding the shells in position beneath theprojections 4!, see particularly Fig. 4.

Arranged in connection with each of the cavities 3?, there is a metallicinlet strip 42 fitted into a suitable recess 43 molded into the mainbody 39. When the removable wall 33 is in position, the inlet strips 42are fixedly retained in position in their recesses 43, see Figs l and6.. The inlet strips 42 are formed of springy metal and have verticalportions 42 extended into the main body away from the removable wall 33,see Fig. 6.

'At one end, each of the vertical portions #2 of "the inlet' strips 42continue into inner portions 42 which have their free ends arranged onthe axes of the shells 39 to be engaged by the I end contacts 40* of thefuses 43, see Figs. 3 and 4, The relationship between the shells 39 andthe inner portions 42 is such that when the fuses 40 are screwed tightlyinto position, theinner portions 42 are flexed just slightly to makegood electrical contact with the end contacts 40 of the fuses as clearlyshown in Figs. 3 and 4.

The ends of the vertical portions 62 of the inlet strips 42 continueinto end portionsdZ which are extended through complementary holes Mformedin the removable wall 33. The outwardly projected end portions 42are provided to be plugged into a conventional electricoutletreceptacle.

Each of the shells 39, as best shown in Fig. 9,

"is formed at its inner end and on one 'side thereof with a laterallyextended lug 49. Provided for each of the shells 39 there is a metallicoutlet One end of each of the outlet strips by means of a pin 5|. Thelugs 49 and outlet "strips 58 are fitted within suitable recesses 52molded within the body. The other ends of portions 58 of the outletstrips 50. The springiness of the contact portions 50 i permits the plugprongs to be forced into the enlarged portions 52 of the recesses and tothenbear rigidly against the sides of the plug prongs. 1 a At one end,the bottom face of the removable wall 33 is formed with a pair of spacedprojections 48, see Figs. 6 and 7, which extendinto the enlargedportions 52 of the recesses 52 and hold the contact portions 50* inposition against the bottom walls of the enlarged portions 52 -of theThe spaced projections 48 also function' to retain the contact portions50 of the outlet strips 50 in alignment with the spaced holes 53 to beengaged by the prongs of the inserted plug. 7

With the contact portions 50* of the outlet strips 50 located within theenlarged portions '52 of the recesses 52 and with the projections 48"engaged with those contact portions 50 it will be appreciated that theshells 39 will be held against possible rotation while the fuses 40 arebeing screwed into and out of the shells. At the same time, when thewall 33 is removed, the sets 'of-inlet strips 42 and outlet strips 50and asso- '-ciated shells 39 can be removed from the respective recessand cavities of the main body 30 for 'than the width of the strips 59'.

cleaning of contact surfaces'orany otherad just- -Ine'ntsthatmayberequired.

"Fromthe foregoing description, it is apparent that thedouble fusedmember of'the present invention provides complete protectionof'any'electrical appliance connected therewith independent of the usualfuses in the source of electric current. i The fuses of the-member arecompletely exposed for replacement whenblown out and if the fuses ofthemember are of lower amperage 'than'those used in the source, the fusesof the receptacle will be blown before the fuses of the main sourceeliminating the need for groping-"in the dark to replace blown fuses ofthe source.

- In the modification of the invention'shown in Figs. and 14,- the fusedreceptacle is of a'slightly different shape. movable wall 33' are of aslightly different shape The mainbody and its reand the cavities 31' forreceiving the fuses are offset with relation to each rather than beingaxially aligned as in the first form of the inven- "-tion.

' To-compensate for the oiTset arrangement of the cavities 31', theinlet-strips '42 and-their 'mounting recesses 43- are of aslightlydiiferent 'shape, but include the same portions as the strips 442 of the first form of the invention.

The holes 53, as in the previous form of the invention, for receivingthe spaced prongs'of the plug of the electric appliance are formed inthe end of the main body 30 opposed to the end from which the endportions 42 of the inlet strips 42.

extend. Inwardly-of the holes 53, the main body is formed with theenlarged portions 52 of'the recesses 52 in which the outlet strips are,3.

located. Within the enlarged portions 52 of the "recesses 52, the outletstrips 50' are formed with end aligned U-shaped contact portions 58 tobe engaged by the prongs of the plug inserted through the openings53.

To permit insertion and removal of the outlet strips 50', the recesses52' are somewhat deeper Therefore, to retain the contact portions 50ofthe outlet strips'50 well down within the enlargedportions 51 of therecesses and in alignment with the holes 53", the inner face of the wall33' is formed -with asecond'set of depending projections 56. Theprojections-56, as shown in Fig. 13, extend into the-enlarged portions52 of the recessestz' and engage the contact portions 5t of the out-'let strips 50ho'lding those contact portions against the base wall ofthe recesses.

In all other respects, the form of the invention shown in Figs. 10 to 14is similar to that illustrated in Figs. 1 to 9 and like referencenumerals identify like parts in all of the views.

' The modification of the invention shown-in Figs. 15 to 21 is designedto use fuses of the cartridge type. The modified double fusedmemberincludes a main body- 56 and a removable walls l The main body 60 andthe removable wallBl are preferably molded of any one of the dielectricmaterials mentioned in connection with thedes'cription of the first formof the invention. The

" removable wall BI is fitted into a recess 62 molded in 'the' top orfront face of the main body GO'and is retained in position by means ofscrews 63, see Figs. 15 and 17. The screws '63 passthrough holes in'the'wall BI and they are threaded into complementary threadedrecesses'formed in the main body 60.

Within the confines of the recess- 82, the main body -60' is formedwithlaterallyspaced longitudinally extending cavities 65 forrecewing-fuses 4i 0f the cartridge type. At 'the t'opof Fig 16 and at the leftside of Fig. 18; "such a cartridge fuse 66" isshown in positionwithinone ofthecavities --65. Onopp'osite sides'of thecavities 65, thematerial of the main block Ellis formed withnotches 61, see Figsx ld to18, providing clearance for-the ends of ones fingers -to'obtain a'gripon the fuses -66 to'pull them o'utof the cavities'65.

' Means is provided-on the inner face of the removable wall 6! forholdingthe'fuses fiii in'position within-the cavities "65. That meanscom- -prisesprojections 68,-see Figs. 17 and18, which depend from theinner faceof the removable wall -6I'into the tops of the cavities '65.-"-As shown "most clearly in FigLiB, the inner e'nds 'of theprojections-68 are rounded to fit over the tops of the fuses 66 securelyretaining-them in position in the cavities 6 5.

*Mount'ed within suitable recesses 69 formed in the mainbody 60 atadjacent ends of the cavities "65, there are electric inlet strips 70.The inlet -strips 10 are formed of springy metallic material and haveflexible'endportions lll 'extend downward withinthe adjacentends of thecavities65 to make-electrical contact with the adjacent end contacts ofthe fuses 66. The other end portions 10* of the inlet'strips 70 arebentto extend at rightangles to the main portion thereof and are-pr0jected'i'romsl0ts "H formed in the'end of the main body '66.

The'end portions 10 are to be plugged into a conventional outletreceptacle.

- Extending from the'opposite sides of the'cavities -65, there areelectric outlet strips 15 located within suitable recesses" formed inthe main body 60. The outlet strips I6 are also formed ofspringy-metallic' material and at one of their ends are'formed'withflexible end portions 76 for making electrical contact with the end capsat the other ends of the fuses 66. Intermediate of their ends, theoutlet stripsl'ii are twisted and have their other ends'bent intoU-shaped contact portions "16 located within enlarged portions H -of therecesses 11. 'The adjacent end of the main *body is formed with spacedholes 18 to admit the spaced prongsof the'plug of theelectrical'appliance to be connected to the source of electriccurrentthrough the fused outlet receptacle.

As in the form of the invention shown in Figs.

10 told, the enlarged portions l'li of the recesses I'l are somewhatdeeper than the width of the U-shaped contactportions 16 of the outletstrips 16. Therefore, the inner face of the removable wall is formedwith a pair of. spaced projections 79;:see particularly Figs. 17 and 19,which engage the U-shaped contact portions 76* holding them against thebase wall of the enlarged-portions 11 of the recesses 'H'andin alignmentwith the holes 'lfi.

: The form of the invention shown in Figs. 15 to 21' provides a doublefused member employing cartridge type fuses which affords completeprotection -to any electrical appliance connected thereto. When thefuses areblown out and require'replacement, the removable wall 6| istaken ofi by removing the screws '63 and then removing and replacing theblown fuse or fuses 66 as the case may be. When replacement is completedthe wallfil is remounted in position to hold all of the "parts of thereceptacle in position in their respective cavities or recesses.

While I have illustrated and described the preferred embodiments of myinvention, it is to be understood that I do not limit myself to theprecise constructions herein disclosed and the right is reserved toallchanges and modifications com,

jtactgwith said fuses-and having-their other ends projected from one endof said body to have a .source, of electric current connected thereto,and outlet strips engaging the lugs of said shells and .;leadingtherefrom to be engaged by the Lspacedprongsofthe insertedplug of anelectric "appliance; said; body having; holes extending throughthejsides'of the main body in axial alignment .with said shells tothreadedly receive screwin1;type fuses ,;ext ended into the body through:saidholes in thesides of the body.- 1

.A double fused member for screw-in type fuses comprising. a: body ofinsulation .material ;.having a removable wall, cavities within saidbody forlfuses, .'a;circular threaded metallic shell positioned'withineach'of said cavities, said shell including a laterally extending lug;means onsaid ;.wall retaining said shells in a fixed position with-.insaidcavities, said retaining means comprising projections dependingfrom, said wall into said cavities, inlet strips having oneof their endspro- .jected into said cavities to make electrical'contact 1.withsaid-fuses and havingtheir other ends projected. from one end of saidbody to have a r source of-electric current connected thereto, andoutlet "strips engaging .the lugs of said shells J and leading:therefrom .to be. engaged by the spaced prongs of the inserted plug ofan electric --appliance, said body having holes extending ---through thesides of the main body in axial alignment with said shells to threadedlyreceive screwin type fusesextended; into the body through said holes inthe sides of the body, each of said shells having a lug extendinglaterally from one side thereof and to which the ends of the outletstrips are secured. a

3..A double fusedmember for screw-in. type fuses comprising a, body ofinsulation material having a removable wall, cavities within said body:.forfuses, a circular threaded metallic shell posiotioned within eachof said cavities, said shell including a laterally extending lug, meanson said wall retaining said shells in a. fixed position .within saidcavities, said retaining means comprising projections depending fromsaid wall into said cavities, inlet strips having one of their endsprojected into said cavities to make electrical contact with said fusesand having their other ends projected from one end of said body to havea source of electric current connected thereto, and outlet stripsengaging the lugs of said shells and leading therefrom to be engaged bythe spaced prongs of the inserted plug of an electric appliance, saidbody having holes extending through the sides of the main body in axialalignment with said shells to threadedly receive screw-1n type fusesextended into the body through said holes in the sides of the body, eachof said shells having a lug extending laterally fuses comprising a bodyof insulation material having a removable wall, cavities within saidbody for-fuses, a circular threaded metallic shell positioned withineachofsaid cavities, said shell in- .cluding a laterally extending lug,means. on said wall retaining said shells in a fixed position. withinsaidcavities, said retaining means comprising projections depending fromsaid wall into said cavities, inlet strips having one of their endsprojected into said cavities to make electrical contact with said fusesand having their other ends projected from oneqend ofsaid .body tohave-.a

source of electriccurrentconnected thereto, and

,outlet strips engaging the lugs of said' shells and leading therefromto be engaged by the spaced prongs of the inserted plug of an electricappliance,- said body having holes extending through the sides of themain body in ,axial alignment with said shells to threadedly receivescrew-in type fuses extended to the body through said'holes in the sidesof the body, said shells being arranged in axial alignment-within saidbody. m

5. A double fused member for screw-in type fusescomprising a body ofinsulation material having a removable wall, cavities within said bodyfor fuses, a circular threaded metallic shell .posi

. tioned within each of said'cavities, saidshell including a laterallyextending-lug, means on .said

, wall retaining said shells in a fixediposition within said cavities,said retaining means comprising projections depending from said wallintosaid cavities, inlet strips having oneof their endsprojected intosaid cavities to make. electricalcontact with said fuses and havingtheir other. endsprojected from one end'of said bodytohave a source ofelectric current connected thereto, and

outlet strips engaging the lugs :of saidv shells and leading therefromto be engaged by the spaced prongs of the inserted plug ofanelectricappliance, said 7 bodyhaving holes, extending through the sides ofthemain body in axialalign- -ment with said shells to threadedly receivescrew-in type fuses extended into .tha body through said holes in thesides of the body, said shells being axially offset from each other'rn6. A double fused-member for ,screw-in type fuses comprising a body ofinsulation material having a removable wall, cavities withinsaid bodyfor fuses, a circular threaded metallicsliell positioned within each ofsaid cavities, said shell including a laterally extending lug, means onsaid wall retaining said shells in a fixed position within saidcavities, said retaining means comprising projections depending fromsaidwall into said cavities, inlet strips having one of their endsprojected into said cavities to make electrical contact with said fusesand having their other ends projected from one end of said body to havea source of electric current connected thereto, and outlet stripsengaging the lugs of said shells and leading therefrom to be engaged bythe spaced prongs of the inserted plug of an electric appliance, saidbody having holes extending through the sides of the main body in axialalignment with said shells to threadedly receive screwin type fusesextended into the body through said holes in the sides of the body, saidoutlet strips References Cited in the file of this patent UNITED STATESPATENTS Number Number Name Date Mattia Aug. 18, 1931 Craoldock Dec. 27,1932 Kelley Mar. 6, 1934 Fried Feb. 5, 1935 Mehrtens Feb. 17, 1948FOREIGN PATENTS Country Date Germany May 15, 1931

